Technological  innovation

The Challenger expedition used simple but robust methods to collect observations and samples: geological dredges and biological nets, water sampling bottles and mercury in glass thermometers for the chemistry and physics of seawater.  Navigation was by star sights and the depth measured by sounding lead line.  Apart from improvements in depth measurement and navigation, methods used by marine scientists barely changed until the late 1960s.  Since then the progress has been dramatic.

Many technology developments for oceanography in the UK from the 1960s to the late 1980s came from the National Institute of Oceanography at Wormley (later the Institute of Oceanographic Sciences), examples of which can be found via the following links 

Acoustic releases
Autosub
Current meter moorings
Data Buoy (DB1)Double Barrelled Capstan/Winch
Geological Long-Range Inclined ASDIC (GLORIA)
Meteorological measuring and recording (Multimet)
Neutrally buoyant floats
Ocean bottom Seismographs
Open Ocean Tide Gauges
Ship-borne Wave Recorder (SBWR)
Towed Ocean Bottom Instrument (TOBI)
 
The stories of other notable technology developments can be found at
Continuous plankton recorder
Marine seismics at University of Cambridge
Tide Prediction Machines  
Sediment corers
Analytical chemistry methods